When i run PS3 mediaserver my computer gets overheated after approx. 30 minutes. I then have to restart the computer.. It has worked for me before but now suddenly it´s struggling. The movie I´m watching is an episode from the serie 24. It´s an .mkv file with 15 gb streaming. I run it via the router and have a cable connection.

Is it possible to adjust the program so the computer won´t be so overheated???

The program Istat menus is saying that the cpu is above 75 Celsius (167 fahrenheit) when it automaticly shuts down

A little more information could be helpful. Which model of mac is it? Are you sure it's shutting down due to heat? 76 degrees C is not that hot for a CPU. I've seen CPUs run from 90-100ºC with no ill effects.

Only two ways to keep a CPU cool:

1) keep the load lighter, i.e. set the transcoding engine to lossless or a setting that is very high bitrate/quality. The higher the transcoding bitrate, the less work the CPU needs to do.

2) Run your fans at a higher rate. Do a google search for an app called "smcFanControl." It's a free app that supports most mac models, and will let you control how fast your fans spin. Set the fans to wind tunnel mode (5500+ rpms), and you should be good.